This package contains the PostgreSQL ODBC driver. Applications
wishingto make use of it need to go through an ODBC driver
manager. On Debian, this normally means that they have a
dependency on the package "libiodbc2" or "unixodbc".

This example came from the need not to programing with ODBC,
easier, use it a connection that's already available in ODBC but
the information in network related are currenly out of date and
very poor also not related at all to debian.

Debian package (odbc-postgresql) actually contains two
drivers, one ANSI variant (psqlodbca) and one
Unicode variant (psqlodbcw). The Unicode variant
works with Unicode and ASCII clients, the ANSI variant should
work with any client encoding provided that the database encoding
matches. The specifics depend on the application and the driver
manager; experimentation may be necessary in some cases

To be able to access a particular database via ODBC you need to
register it as an ODBC data source. Data sources are registered
globally in /etc/odbc.ini or for each user in private home
file as ~/.odbc.ini respectively.

The
loop devices are useful, are unique to Linux systems only, other
precary operating systems require tirhd party utilities, this
type of software exist on all Linux distros, it is part of their
base and has nothing to do with things GNU as owes its management
to the kernel.